Dehydration in the Breastfed Baby

Signs, Causes, Treatment, and Prevention of Dehydration in Newborns and Infants

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Woman taking baby's temperature
Illness or fever can lead to dehydration in newborns and infants. Tetra Images/Getty Images


Dehydration is a condition where the there is not enough fluids in the body. Your baby's body is made up of approximately 75% water. Each day, your child loses fluids through urination, bowel movements, sweating, crying, and even breathing. And, every time you breastfeed your baby, these fluids are replaced. However, if an infant loses more fluids than he or she takes in, it can lead to dehydration.


  • Dry lips
  • Dry mouth
  • Less than 6 wet diapers in a 24 hour period
  • No interest in breastfeeding
  • A sunken fontanel (soft spot) on your baby's head
  • No tears when your baby is crying
  • Irritability


Not Breastfeeding Often or Long Enough: A breastfed newborn should be nursing at least 8-12 times each day (throughout the day and night). If your baby is not waking up for feedings, you should be waking him up.

A Poor Breastfeeding Latch: If your little one is not latching on correctly, he cannot remove the breast milk from your breasts so he may not get enough.

A True Low Breast Milk Supply: If your baby is latching on correctly and nursing every 2-3 hours around the clock but still not getting enough breast milk, there could be an underlying issue causing a true low milk supply.

Breast Refusal: A baby who is refusing to breastfeed is not taking in fluids and can quickly become dehydrated.

Illness: A sick child may have difficulty at the breast. A stuffy nose, pain, and irritability can all interfere with breastfeeding.

Fever: A rise in your child's body temperature can cause a greater loss of fluids. Plus, your baby may not breastfeed as well when he has a fever.

Diarrhea: Diarrhea is not common in breastfed newborns since breastfeeding actually helps to prevent infant diarrhea. However, if your child does develop diarrhea, the loss of fluids through the bowels can be dangerous.

Overexposure to Heat: Very high temperatures, extreme humidity, or spending too much time outdoors in the hot sun, can cause sweating and the evaporation of fluids through your baby's skin.


The treatment for infant dehydration depends on the cause and severity of the dehydration. If your child is only mildly dehydrated, you may just have to breastfeed more often and monitor your baby closely. But, if your baby has an illness and the dehydration becomes severe, hospitalization with IV fluids may be required. 


  • Breastfeed your baby every 2 – 3 hours around the clock. If you have a sleepy baby, wake him up to breastfeed.
  • Evaluate your baby's latch. Make sure your baby is latching on correctly so that you can be sure he is getting enough breast milk as he nurses. If you cannot tell if your baby is latching on correctly, look for the signs of a good latch vs. a poor latch and talk to your doctor, a lactation consultant or a local breastfeeding group for assistance.
  • Monitor your baby for signs that she is getting enough breast milk. Keep track of the number of wet and dirty diapers your baby has each day and have your child's weight monitored by the pediatrician.
  • Avoid bringing your newborn or young infant outdoors in extreme heat or high humidity. If you need to be outside, keep your baby in the shade and as cool as possible. Also, breastfeed very often to keep replacing the fluids that your baby is losing.
  • If your child is sick or has diarrhea for more than 24 hours, see your baby's doctor for treatment and monitoring.  Continue to breastfeed as often as possible while your child is undergoing treatment.

    When to Call the Doctor

    Dehydration in breastfed infants is not common, but it can happen. Severe dehydration can be a very dangerous and even life-threatening situation for your baby. If your child has a fever, is not breastfeeding well, or shows any of the signs of dehydration listed above, contact your child's doctor immediately.   

    View Article Sources
    • American Academy of Pediatrics. New Mother’s Guide To Breastfeeding. Bantam Books. New York. 2011.
    • Cadwell, Karin, Turner-Maffei, Cynthia, O'Connor, Barbara, Cadwell Blair, Anna, Arnold, Lois D.W., and Blair Elyse M. Maternal and Infant Assessment for Breastfeeding and Human Lactation A Guide for the Practitioner Second Edition. Jones and Bartlett Publishers. 2006.
    • Lawrence, Ruth A., MD, Lawrence, Robert M., MD. Breastfeeding A Guide For The Medical Profession Seventh Edition.  Mosby. 2011.
    • Riordan, J., and Wambach, K. Breastfeeding and Human Lactation Fourth Edition. Jones and Bartlett Learning. 2014.